Clinical experience over 48 years with pheochromocytoma

Two cases of atraumatic adrenal hemorrhage: A review of active management, conservative management, and challenges faced

Adrenal hemorrhage (AH) is an uncommon and potentially disastrous affliction that carries an accepted mortality risk of 15%. Variable symptomatology can cause a diagnostic dilemma and may be missed. We present 2 cases of right-sided AH; both cases were initially presumed to be renal colic. Case 1 was an 86-year-old gentleman, presenting with right flank pain found to have a right-sided atraumatic AH. He presented with hemorrhagic shock, requiring angioembolization of the bleeding vessel. Case 2 was a 62-year-old gentleman who presented with right flank pain and was found to have a right-sided atraumatic AH. He was hemodynamically stable and successfully managed conservatively. Adrenal hemorrhage is a potentially fatal affliction that may be missed. CT scans are the recommended imaging modality during an acute presentation due to wider availability and fast assessment. We demonstrate a hemodynamically stable patient managed with a 'watch and wait' approach and an unstable patient managed with resuscitation followed by urgent angioembolization.

Case of functional paraganglioma with intraoperative hypertensive crisis during robot-assisted thoracoscopic resection

BACKGROUND

Mediastinal paragangliomas are rare. Their dangerousness may unfold during surgery, especially if hormonal activity was previously unknown. We report our experience with this case in context to the incidence and localization of atypically located mediastinal paragangliomas in the literature.

CASE PRESENTATION

A 69-year-old female patient who was scheduled for thoracoscopic resection due to a posterior mediastinal tumor that had been progressing in size for several years and increasing symptoms. The induction of anesthesia, the ventilation of the lungs and the gas exchange after lung separation was uneventful. After initially stable circulatory conditions, there was a sudden increase in blood pressure up to 300/130 mmHg and tachycardia up to 130/min. This hypertensive phase was difficult to influence and required a rapid and consistent use of antihypertensive medication to bring down the blood pressure to reasonable values. The patient stabilized after tumor resection. The postoperative course was unremarkable. During the intraoperative blood pressure crisis, blood was drawn for analysis. These samples showed elevated concentrations of normetanephrine and metanephrine. The tumor subsequently presented as a catecholamine-secreting paraganglioma.

CONCLUSION

In order to avoid life-threatening blood pressure crises, hormone activity should be ruled out preoperatively in the case of mediastinal tumor, in which a paraganglioma could be considered in the differential diagnosis, especially if there are indications of hypertension in the medical history. Robotic-assisted thoracoscopic resection of the posterior mediastinal tumor was a feasible surgical method, even in the case of unexpected functional paraganglioma.

Comprehensive Investigation of Angiogenesis, PASS Score and Immunohistochemical Factors in Risk Assessment of Malignancy for Paraganglioma and Pheochromocytoma

A challenging task in routine practice is finding the distinction between benign and malignant paragangliomas and pheochromocytomas. The aim of this study is to conduct a comparative analysis of angiogenesis by assessing intratumoral microvascular density (MVD) with immunohistochemical (IHC) markers (CD31, CD34, CD105, ERG), and S100 immunoreactivity, Ki67 proliferative index, succinate dehydrogenase B (SDHB) expressiveness, tumor size with one the most utilized score Pheochromocytoma of Adrenal Gland Scales Score (PASS), using tissue microarray (TMA) with 115 tumor samples, 61 benign (PASS < 4) and 54 potentially malignant (PASS ≥ 4). We found no notable difference between intratumoral MVD and potentially malignant behavior. The group of potentially malignant tumors is significantly larger in size, has lower intratumoral MVD, and a decreased number of S100 labeled sustentacular cells. Both groups have low proliferative activity (mean Ki67 is 1.02 and 1.22, respectively). Most tumors maintain SDHB expression, only 6 cases (5.2%) showed a loss of expression (4 of them in PASS < 4 group and 2 in PASS ≥ 4). PASS score is easily available for assessment and complemented with markers of biological behavior to complete the risk stratification algorithm. Size is directly related to PASS score and malignancy. Intratumoral MVD is extensively developed but it is not crucial in evaluating the malignant potential.

177 Lu-DOTATATE in the Treatment of Recurrent Pheochromocytoma With Multiple Metastases

ABSTRACT

The treatment of metastatic pheochromocytoma is challenging. We report a case of a woman with recurrent pheochromocytoma with multiple metastases who achieved excellent response after 4 cycles of 177 Lu-DOTATATE therapy. She did not experience any observable adverse effects. Her disease was still stable 6 months after the fourth cycle of treatment.

Three Dimensional Models of Endocrine Organs and Target Tissues Regulated by the Endocrine System

Immortalized cell lines originating from tumors and cultured in monolayers in vitro display consistent behavior and response, and generate reproducible results across laboratories. However, for certain endpoints, these cell lines behave quite differently from the original solid tumors. Thereby, the homogeneity of immortalized cell lines and two-dimensionality of monolayer cultures deters from the development of new therapies and translatability of results to the more complex situation in vivo. Organoids originating from tissue biopsies and spheroids from cell lines mimic the heterogeneous and multidimensional characteristics of tumor cells in 3D structures in vitro. Thus, they have the advantage of recapitulating the more complex tissue architecture of solid tumors. In this review, we discuss recent efforts in basic and preclinical cancer research to establish methods to generate organoids/spheroids and living biobanks from endocrine tissues and target organs under endocrine control while striving to achieve solutions in personalized medicine.

Long-Term Outcomes after Surgery for Pheochromocytoma and Sympathetic Paraganglioma

BACKGROUND

The prognosis of pheochromocytoma and sympathetic paraganglioma (PHEO/sPGL) is difficult to predict at the time of diagnosis and long-term follow-up data are scarce, especially for apparently benign and sporadic variants. The aim of the study was to analyze the long-term outcomes in PHEO/sPGL patients.

METHODS

A monocentric series of 170 patients who underwent surgery for PHEO/sPGL was analyzed.

RESULTS

The study cohort included 91 female and 79 males with a median age of 48 years (range 6-83). The majority of PHEO/sPGL cases were considered apparently benign at the time of diagnosis; evident malignant behavior was found in 5% of cases. The overall 10-year risk of recurrence was 13%, but it rose up to 33% at 30 years. The risk of new tumor recurrence was higher in patients with hereditary tumors, but the risk was still significant in patients with apparently sporadic variants (20-year risk: 38% vs. 6.5%, respectively; p < 0.0001). The risk of metastatic recurrence was higher in patients with locally aggressive tumors at diagnosis, but the risk was present also in apparently benign variants (5-year risk: 100% vs. 1%, respectively; p < 0.0001).

CONCLUSIONS

Lifelong follow-up is required not only for hereditary PHEO/sPGL but also for apparently benign and sporadic tumors at diagnosis because of the risk of long-term recurrent disease.

Repeat hepatectomy for massive liver metastases from pheochromocytoma: a case report

In malignant pheochromocytoma, the survival benefit of metastasectomy remains unclear. However, excessive catecholamines secreted from pheochromocytomas can cause cardiovascular and cerebrovascular complications. Debulking metastasectomy can be performed to reduce excess catecholamine secretion when curative resection is impossible. We present a case of metastatic pheochromocytoma to the liver, wherein a significant reduction in catecholamine secretion was achieved by repeat debulking hepatectomy. A 62-year-old woman who had undergone left adrenalectomy for primary pheochromocytoma 10 years prior to our surgical management, had multiple liver metastases of pheochromocytoma. Curative hepatectomy was infeasible because of insufficient remnant liver volume; thus, debulking hepatectomy was conducted. Preoperatively, increased doses of alpha-blockers and catecholamine synthesis inhibitors were administered. Nevertheless, substantial fluctuations in blood pressure and massive hemorrhage were observed intraoperatively. Eight months after the initial hepatectomy, repeat hepatectomy for the remnant lesions was performed due to the worsening of catecholamine levels and catecholamine-related symptoms. The patient survived, with serum catecholamines remaining within the normal range after repeat hepatectomy. Repeat debulking hepatectomy for metastatic pheochromocytoma to the liver is a feasible treatment strategy to effectively decrease catecholamine secretion and alleviate the symptoms thereof. However, special attention should be paid to perioperative catecholamine management and intraoperative surgical techniques.

Bladder paraganglioma: A case of acute respiratory distress syndrome triggered by large bladder tumor transurethral resection with mild symptoms and atypical imaging

Introduction

Bladder paraganglioma is exceedingly rare, accounting for <0.05% of bladder tumors. This is a case of paraganglioma with no symptom other than palpitations during urination, with atypical imaging, resulting in acute respiratory distress syndrome after transurethral resection of the bladder tumor.

Case presentation

A 46-year-old man underwent transurethral resection of the bladder tumor for a bladder tumor 61 × 52 mm in size on contrast-enhanced computed tomography. The patient only had micturition attacks and was suspected to have urothelial carcinoma on magnetic resonance imaging. The patient had acute respiratory distress syndrome after the operation which improved conservatively. The ¹²³Iodine metaiodobenzylguanidine scintigraphy, urinalysis, and pathological examination revealed bladder paraganglioma. Robot-assisted radical cystectomy and ileal neobladder reconstruction were performed.

Conclusion

This study reported bladder paraganglioma with no symptoms other than micturition attacks in which acute respiratory distress syndrome occurred after transurethral resection of the bladder tumor.

Tips and Tricks in Laparoscopic Adrenalectomy for Pheochromocytoma. How We Do It

"Pheochromocytomas are rare neuroendocrine tumors that frequently have genetic involvement and can present a particular risk in terms of the anesthetic-surgical procedure. Current worldwide medical recommendations state that laparoscopic adrenalectomy is the conventional treatment for pheochromocytoma, however, the ideal surgical strategy is still being developed as specialized surgeons gain experience with these rare tumors. The study's purpose was to thoroughly evaluate our film library and identify the best surgical steps that represent our standardized procedure. We developed a comprehensive set of surgical critical strategies for either a left or right adrenalectomy, providing helpful advice on patient positioning, port placement, the adrenal gland approach, as well as other surgical methods specifically designed for tumor mobilization and dissection. The current paper aims to synthesize our clinical experience in terms of preoperative preparation, patient positioning, intraoperative complications, causes of conversion, and specimen extraction. The main conclusions concern both the best surgical approach and the importance of surgical experience in the clinical management of these rare tumor types. "

Influence of duration of preoperative treatment with phenoxybenzamine and secretory phenotypes on perioperative hemodynamics and postoperative outcomes in pheochromocytoma and paraganglioma

Objectives

Resection of pheochromocytoma and paraganglioma (PPGL) carries risks with perioperative hemodynamic instability. Phenoxybenzamine (PXB) is a commonly used α-blockade to prevent it. It is unclear whether lengthening the preoperative duration of PXB is better for hemodynamic stability and postoperative outcomes. Furthermore, different types of catecholamines have varying effects on perioperative hemodynamics. Thus, our study aimed to investigate the impact of the duration of preoperative preparation with PXB and secretory phenotypes of the patients on intraoperative hemodynamic stability and postoperative complications in PPGL.

Methods

Between Dec 2014 and Jan 2022, 166 patients with PPGL were operated on by the same team at Sun Yat-sen Memorial Hospital. They were divided into group A(1-14d), Group B(15-21d), and Group C(>21d) based on the duration of management with PXB and into the adrenergic and the noradrenergic phenotype group based on secretory profiles. Data on intraoperative hemodynamics and postoperative outcomes were collected and compared among groups.

Results

A total of 96 patients occurred intraoperative hemodynamic instability, and 24 patients had 29 postoperative complications related to the surgery. Among the 145 patients treated with PXB, no significant differences were found in the cumulative time outside the target blood pressure(6.67%[0-17.16%] vs. 5.97%[0-23.08%] vs. 1.22%[0-17.27%], p=0.736) or in the median total HI-score(42.00[30.00-91.00] vs. 89.00[30.00-113.00] vs. 49.00[30.00-93.00], p=0.150) among group A(n=45), B(n=51) and C(n=49). Multivariate analysis demonstrated that the level of plasma-free metanephrine(MN) was an independent risk factor for intraoperative hemodynamic instability. And the median cumulative time outside of the target blood pressure in the adrenergic phenotype group was significantly greater than that in the noradrenergic phenotype group(8.17%[0-26.22%] vs. 1.86%[0-11.74%], p=0.029). However, the median total HI-score(99.50[85.00-113.25] vs. 90.00[78.00-105.00], p=0.570) and postoperative outcomes showed no differences between the two groups.

Conclusions

A preoperative duration of nearly 14 days with PXB is sufficient for ensuring intraoperative hemodynamic stability in PPGL. And lengthening the preparation duration may not provide additional benefits in the era of widespread application and advanced techniques of laparoscopic surgery. Additionally, patients with the adrenergic phenotype are more prone to intraoperative hemodynamic instability than the noradrenergic phenotype. Thus, more attention should be given to the adrenergic phenotype during surgery.

Primary Functioning Hepatic Paraganglioma Treated by Laparoscopy: A Case Report

Paragangliomas are highly vascularised and often heritable tumors derived from the paraganglia. They are typically discovered in the retroperitoneal space as well as the head and neck region but are rarely encountered in the liver parenchyma. We report a case of a primary functioning hepatic paraganglioma and provide an up-to-date literature review of patients with such tumors. We present a case of functioning paraganglioma in a 34-year-old female patient who suffered a solitary lesion in her left lateral lobe with symptoms of hypertension since pregnancy. She did not have any family history and her pre-pregnancy examination was negative. An abdominal CT imaging revealed a 6.5 × 5.7 cm liver lesion in segments II and III. Laboratory investigations identified elevation in plasma-free catecholamines. With sufficient preoperative preparation, the patient underwent laparoscopic left hemihepatectomy. Immunohistochemical staining revealed Syn (+) tumor cell nests surrounded by S-100 sustentacular cells (+), providing a definitive diagnosis of paraganglioma. The patient recovered uneventfully without signs of recurrence during a 1-year follow-up period. Our case demonstrates that primary refractory hypertension in pregnancy should be screened for paraganglioma through abdominal ultrasound and plasma free catecholamines. On the other hand, laparoscopic surgery is technically safe and feasible for the treatment of patients with hepatic paragangliomas in favorable locations.

Targeted Therapies in Pheochromocytoma and Paraganglioma

Molecular targeted therapy plays an increasingly important role in the treatment of metastatic pheochromocytomas and paragangliomas (PPGLs), which are rare tumors but remain difficult to treat. This mini-review provides an overview of established molecular targeted therapies in present use, and perspectives on those currently under development and evaluation in clinical trials. Recently published research articles, guidelines, and expert views on molecular targeted therapies in PPGLs are systematically reviewed and summarized. Some tyrosine kinase inhibitors (sunitinib, cabozantinib) are already in clinical use with some promising results, but without formal approval for the treatment of PPGLs. Sunitinib is the only therapeutic option which has been investigated in a randomized placebo-controlled clinical trial. It is clinically used as a first-, second-, or third-line therapeutic option for the treatment of progressive metastatic PPGLs. Some other promising molecular targeted therapies (hypoxia-inducible factor 2 alpha [HIF2α] inhibitors, tumor vaccination together with checkpoint inhibitors, antiangiogenic therapies, kinase signaling inhibitors) are under evaluation in clinical trials. The HIF2α inhibitor belzutifan may prove to be particularly interesting for cluster 1B-/VHL/EPAS1-related PPGLs, whereas antiangiogenic therapies seem to be primarily effective in cluster 1A-/SDHx-related PPGLs. Some combination therapies currently being evaluated in clinical trials, such as temozolomide/olaparib, temozolomide/talazoparib, or cabozantinib/atezolizumab, will provide data for novel therapy for metastatic PPGLs. It is likely that advances in such molecular targeted therapies will play an essential role in the future treatment of these tumors, with more personalized therapy options paving the way towards improved therapeutic outcomes.

A 15-year pheochromocytoma and paraganglioma experience in a single centre: a Singapore perspective

Introduction

Pheochromocytomas (PCC) and paragangliomas (PGL) are rare endocrine tumours. The objective of this study was to describe our experience with these two entities in a Singapore population.

Methods

We identified patients with positive histopathological confirmations of PCC and PGL who were treated at a tertiary Singapore hospital between January 2000 and December 2015. The results were analysed for clinical presentations, treatment and long-term outcomes.

Results

A total of 27 cases (20 PCC, 7 PGL) were identified over a 15-year period. One case of PGL developed bilateral disease on follow-up. There were 17 male and 10 female patients with a median age of 57 (range 24-77) years. A positive family history was uncommon and present in only 3.7% of patients. Uniquely, the top three presenting symptoms were abdominal discomfort, palpitations and diaphoresis. Despite adequate preoperative preparation, intraoperative haemodynamic instability occurred in 70.4% and early postoperative hypotension occurred in 11.1% of patients. After surgery, hypertension was resolved in 41.2% (7/17) and diabetes mellitus in 60% (3/5). Disease recurrence was reported in 22.2% and distant metastases in 14.8%. At the end of the follow-up period (median 35 [range 3-148] months), 70.4% were still alive.

Conclusion

PCC and PGL can present with a wide range of symptoms. Intraoperative haemodynamic instability was frequent despite good preoperative preparation. Disease recurrences and metastasis occurred in up to one-fifth of the patients. Genetic screening should be offered to patients with PCC and PGL.

Management of Patients with Treatment of Pheochromocytoma: A Critical Appraisal

Simple Summary

Preoperative medical preparation with an alpha blockade has been implemented early 1960s to prevent intraoperative hemodynamic instability and consequently decrease morbi-mortality in patients at a high risk of complications. Indeed, surgery at that time consisted of open adrenalectomies with a high morbidity and mortality rate. Current clinical guidelines are based on these early experiences. However, emerging technologies have permitted a drastic reduction of the morbi-mortality rate in patients treated for pheochromocytoma. However, the clinical guidelines have not evolved at the same rate. The aim of this systematic review is to assess the evolution of the management of pheochromocytomas and to appraise the current clinical guidelines to the current clinical practices.

Abstract

The management of pheochromocytomas has significantly evolved these last 50 years, especially with the emergence of new technologies such as laparoscopic procedures in the 1990s. A preoperative blockade using antihypertensive medications to prevent intraoperative hemodynamic instability and cardiocirculatory events is recommended by current clinical guidelines. However, these guidelines are still based on former experiences and are subject to discussion in the scientific community. The aim of this systematic review was to assess the evolution of the management of pheochromocytomas. Laparoscopic procedure is established as the standard of care in current practices. Preoperative medical preparation should be questioned because it does not significantly improve intraoperative events or the risk of postoperative complications in current clinical practice. Current clinical recommendations should be revised and upgraded to current clinical practices.

Benign Neurogenic Tumors

Neurogenic tumors arise from cells of the nervous system. These tumors can be found anywhere along the distribution of the sympathetic and parasympathetic nervous system and are categorized based on cell of origin: ganglion cell, paraganglion cell, and nerve sheath cells. Ganglion cell-derived tumors include neuroblastomas, ganglioneuroblastomas, and ganglioneuromas. Paraganglion cell-derived tumors include paragangliomas and pheochromocytomas. Nerve sheath cell-derived tumors include schwannomas (neurilemmomas), neurofibromas, and neurofibromatosis. Most of these are benign; however, they can cause local compressive symptoms. Surgery is the mainstay of treatment, if clinically indicated. Nonetheless, a thorough preoperative workup is essential, especially for catecholamine-secreting tumors.

Comparison of preoperative alpha-blockade for resection of paraganglioma and pheochromocytoma

OBJECTIVE

Phenoxybenzamine (nonselective, non-competitive alpha-blocker) is the preferred drug for preoperative treatment of pheochromocytoma, but doxazosin (selective, competitive alpha-blocker) may be equally effective. We compared the efficacy of doxazosin versus phenoxybenzamine.

METHODS

We conducted a prospective study of patients undergoing pheochromocytoma or paraganglioma resection by randomizing pretreatment with phenoxybenzamine or doxazosin at a single tertiary referral center. The high cost of phenoxybenzamine led to high crossover to doxazosin. Randomization was halted, and a consecutive historical cohort of phenoxybenzamine patients was included for a case-control study design. The efficacy of alpha-blockade was assessed with pre-induction infusion of incremental doses of phenylephrine. The primary outcomes were mortality, cardiovascular complications, and ICU admission. Secondary outcomes were hemodynamic instability index (proportion of operation outside of hemodynamic goals), adequacy of blockade by phenylephrine titration test, and drug costs.

RESULTS

Twenty-four patients were prospectively enrolled (doxazosin, n=20; phenoxybenzamine, n=4), and 15 historical patients treated with phenoxybenzamine were added (total phenoxybenzamine, n=19). No major cardiovascular complications occurred in either group. The phenylephrine dose-response curves showed less blood pressure rise in the phenoxybenzamine than the doxazosin group (linear regression coefficient 0.008 versus 0.018, P=.01), suggesting better alpha-blockade in the phenoxybenzamine group. Median hemodynamic instability index was 14% versus 13% in the phenoxybenzamine and doxazosin groups, respectively (P=.56). The median highest daily cost of phenoxybenzamine was $442.20 compared to $5.06 for doxazosin.

CONCLUSION

Phenoxybenzamine may blunt intraoperative hypertension better than doxazosin, but this difference did not translate to fewer cardiovascular complications and is offset by a considerably increased cost.

Bilateral adrenal uptake of 123I MIBG scintigraphy with mild catecholamine elevation, the diagnostic dilemma, and its characteristics

Cases in which bilateral adrenal ¹²³I-Metaiodobenzylguanidine (¹²³I-MIBG) scintigraphy accumulation is sometimes shown, with mildly elevated catecholamine (CA) or metanephrine (MN) levels (within 3 times the upper reference limit) are diagnostic dilemmas. We experienced 3 cases of adrenal incidentalomas with this dilemma in the differential diagnosis. The clinical diagnosis was subclinical Cushing's syndrome in 2 cases, and primary aldosteronism in 1. Despite suspected CA excess in clinical symptoms and imaging findings, the pathological findings of all these tumors were revealed to be cytochrome P450 family 11 subfamily B member 1 (CYP11B1) positive adrenocortical adenomas. Interestingly, adrenal medullary hyperplasia (AMH) was detected in the adrenal parenchyma of all those backgrounds. To clarify the clinical features of such cases, a cross-sectional study was conducted at the Kobe University Hospital from 2014 to 2020. One-hundred sixty-four patients who had undergone ¹²³I-MIBG scintigraphy were recruited. Among them, 10 patients (6.1%) met the above criteria, including the presented 3 cases. Plasma adrenaline, noradrenaline, urinary metanephrine, and normetanephrine had values of 0.05 ± 0.05 ng/mL, 0.63 ± 0.32 ng/mL, 0.22 ± 0.05 mg/day, and 0.35 ± 0.16 mg/day, respectively. Nine cases were complicated with hypertension, and symptoms related to CA excess were observed. Half of them (5 cases) including presented 3 cases had unilateral adrenal tumors. These suggest that in cases of bilateral adrenal uptake on ¹²³I-MIBG, AMH needs to be considered. Adrenocortical adenomas may be associated with AMH and further larger investigation is needed for this pathology.

Preoperative blood pressure targets and effect on hemodynamics in pheochromocytoma and paraganglioma

Patients with pheochromocytoma and paraganglioma (PPGL) are treated with α-adrenoceptor antagonists to improve peroperative hemodynamics. However, preoperative blood pressure targets differ between institutions. We retrospectively compared per- and postoperative hemodynamics in 30 patients with PPGL that were pretreated with phenoxybenzamine aiming at different blood pressure targets at two separate endocrine departments. All patients were subsequently undergoing laparoscopic surgery at Department of Urology, Herlev University hospital. Fourteen patients were treated targeting to symptomatic and significant orthostatic hypotension and 16 patients to a seated blood pressure below 130/80 mmHg. As a control group, we included 34 patients undergoing laparoscopic adrenalectomy for other reasons. The group titrated to orthostatic hypotension required a higher dose of phenoxybenzamine to achieve the blood pressure target. This group had less intraoperative systolic and diastolic blood pressure fluctuation (Mann-Whitney U test; P < 0.05) and less periods with heart rate above 100 b.p.m. (Mann-Whitney U test; P = 0.04) as compared to the group with a preoperative blood pressure target below 130/80 mmHg. Peroperative use of intravenous fluids were similar between the two groups, but postoperatively more intravenous fluids were administered in the group with a target of ortostatism. Overall, the control group was more hemodynamic stable as compared to either group treated for PPGL. We conclude that phenoxybenzamine pretreatment targeting ortostatic hypotension may improve peroperative hemodynamic stability but causes a higher postoperative requirement for intravenous fluids. Overall, PPGL surgery is related to greater hemodynamic instability compared to adrenalectomy for other reasons.

Controversies about the systematic preoperative pharmacological treatment before pheochromocytoma or paraganglioma surgery

The question of systematic use of a pharmacological treatment before surgery in patients diagnosed with pheochromocytoma and paraganglioma (PPGL) remains highly controversial. While recent guidelines suggest that this should be used in all patients, some experienced teams consider it unnecessary in some cases, provided the surgery is performed in a dedicated center that has expert endocrinologists, cardiologists, surgeons, and anesthetists. This controversy is aimed at shedding light on the potential benefits and risks of such a treatment, focusing specifically on alpha blockers which are considered as the first-line medical treatments in patients with PPGL. After discussing the rationale for alpha blockers, hemodynamic instability, tolerance, and acute cardiac complications will then be discussed in the first part of the manuscript, defending a systematic use. The second section will focus on blood pressure control, tolerance of alpha blockers, and also the management of normotensive PPGL, examining the daily risks of PPGL and arguing against the systematic use of a preoperative pharmacological treatment before surgery. Finally, we will discuss the concept of expert centers and define the patients in whom the risk/benefit profile would favor the use of this preoperative treatment.

Personalized Management of Pheochromocytoma and Paraganglioma

Pheochromocytomas/paragangliomas are characterized by a unique molecular landscape that allows their assignment to clusters based on underlying genetic alterations. With around 30% to 35% of Caucasian patients (a lower percentage in the Chinese population) showing germline mutations in susceptibility genes, pheochromocytomas/paragangliomas have the highest rate of heritability among all tumors. A further 35% to 40% of Caucasian patients (a higher percentage in the Chinese population) are affected by somatic driver mutations. Thus, around 70% of all patients with pheochromocytoma/paraganglioma can be assigned to 1 of 3 main molecular clusters with different phenotypes and clinical behavior. Krebs cycle/VHL/EPAS1-related cluster 1 tumors tend to a noradrenergic biochemical phenotype and require very close follow-up due to the risk of metastasis and recurrence. In contrast, kinase signaling-related cluster 2 tumors are characterized by an adrenergic phenotype and episodic symptoms, with generally a less aggressive course. The clinical correlates of patients with Wnt signaling-related cluster 3 tumors are currently poorly described, but aggressive behavior seems likely. In this review, we explore and explain why cluster-specific (personalized) management of pheochromocytoma/paraganglioma is essential to ascertain clinical behavior and prognosis, guide individual diagnostic procedures (biochemical interpretation, choice of the most sensitive imaging modalities), and provide personalized management and follow-up. Although cluster-specific therapy of inoperable/metastatic disease has not yet entered routine clinical practice, we suggest that informed personalized genetic-driven treatment should be implemented as a logical next step. This review amalgamates published guidelines and expert views within each cluster for a coherent individualized patient management plan.

Johnson and Johnson COVID-19 Vaccination Triggering Pheochromocytoma Multisystem Crisis

Pheochromocytomas are rare tumors that may have variable presentations. The presentation may depend on the type of catecholamine secreted, whether there is a paraneoplastic syndrome or not, or some other factor which may not be well understood. One rare presentation is a pheochromocytoma multisystem crisis. Many of these tumors are asymptomatic and found incidentally, but some can be triggered after being previously dormant. In this case report, we describe the first case of pheochromocytoma multisystem crisis triggered by the Johnson and Johnson (J&J) coronavirus disease 2019 (COVID-19) vaccine. We describe a case of a 63-year-old Caucasian male who presented with intractable nausea, vomiting, dyspnea, watery diarrhea, chills, sweats, and heavy chest pain starting one day status post J&J COVID-19 vaccination. He had no symptoms prior to this and no significant past medical history besides daily marijuana use. During his hospital stay, he had persistent high fevers, respiratory failure, cardiogenic shock, cardiomyopathy, and labile blood pressure measurements. After a retroperitoneal ultrasound, he was found to have a 7 cm mass in the right adrenal gland with elevated chromogranin A, urine vanillylmandelic acid (VMA), and urinary 24-hour metanephrines to confirm the diagnosis of a pheochromocytoma.

Strategies for Targeting Serine/Threonine Protein Phosphatases with Small Molecules in Cancer

Among numerous posttranslational regulation patterns, phosphorylation is reversibly controlled by the balance of kinases and phosphatases. The major form of cellular signaling involves the reversible phosphorylation of proteins on tyrosine, serine, or threonine residues. However, altered phosphorylation levels are found in diverse diseases, including cancer, making kinases and phosphatases ideal drug targets. In contrast to the success of prosperous kinase inhibitors, design of small molecules targeting phosphatase is struggling due to past bias and difficulty. This is especially true for serine/threonine phosphatases, one of the largest phosphatase families. From this perspective, we aim to provide insights into serine/threonine phosphatases and the small molecules targeting these proteins for drug development, especially in cancer. Through highlighting the modulation strategies, we aim to provide basic principles for the design of small molecules and future perspectives for the application of drugs targeting serine/threonine phosphatases.

Malignant pheochromocytoma: A diagnostic and therapeutic dilemma

Introduction

Malignant pheochromocytomas are rare endocrine tumors that develop within chromaffin tissue. The diagnosis of malignancy is based on neoplastic recurrence or the presence of metastasis in organs that lack chromaffin tissue. We report a series of four cases because of their diagnostic and therapeutic particularities.

Presentation of case

we describe four clinical cases of patients with malignant pheochromocytoma whose Menard triad “headache-palpitations-sweating” was present in three out of four patients, the methoxylated derivatives were measured in 4 patients, 3 of which had high values, all of our patients carried out a CT scan which objectified signs of malignancy, MRI was performed on a single patient; presenting with a neoplastic recurrence; looking for a locoregional invasion.

Discussion

Pheochromocytoma (PC) is a rare neuroendocrine tumor derived from the chromaffin cells of the adrenal medulla. Its annual incidence is 2 to 8 per million adults. A peak frequency is observed between 30 and 40 years of age. Approximately 10% of pheochromocytomas are malignant and in 10% of cases, bilateral localization is observed. Criteria for malignancy include the invasion of neighboring organs, a large tumor, the presence of lymphadenopathy on imaging, or fixation on scintigraphy. Surgery for MAP is not always curative. In the case of multiple liver metastases, treatment is based on adrenalectomy, which can be effectively combined with chemoembolization, cryoablation, or radiofrequency techniques.

Conclusion

The main prognostic factors of the malignant pheochromocytomas are a large tumor volume, the existence or number of visceral metastases, and the presence of a mutation in the SDHB (Succinate dehydrogenase B) gene.

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Malignant pheochromocytomas are rare endocrine tumors that develop within chromaffin tissue.

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A very large part of pheochromocytomas are of genetic origin which can be part of hereditary syndromes.

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Criteria for malignancy include the invasion of neighboring organs, a large tumor, the presence of lymphadenopathy on imaging, or fixation on scintigraphy.

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Adequate management of this pathology requires a multidisciplinary consultation meeting

Diagnosis for Pheochromocytoma and Paraganglioma: A Joint Position Statement of the Korean Pheochromocytoma and Paraganglioma Task Force

Pheochromocytoma and paraganglioma (PPGLs) are rare catecholamine-secreting neuroendocrine tumors but can be life-threatening. Although most PPGLs are benign, approximately 10% have metastatic potential. Approximately 40% cases are reported as harboring germline mutations. Therefore, timely and accurate diagnosis of PPGLs is crucial. For more than 130 years, clinical, molecular, biochemical, radiological, and pathological investigations have been rapidly advanced in the field of PPGLs. However, performing diagnostic studies to localize lesions and detect metastatic potential can be still challenging and complicated. Furthermore, great progress on genetics has shifted the paradigm of genetic testing of PPGLs. The Korean PPGL task force team consisting of the Korean Endocrine Society, the Korean Surgical Society, the Korean Society of Nuclear Medicine, the Korean Society of Pathologists, and the Korean Society of Laboratory Medicine has developed this position statement focusing on the comprehensive and updated diagnosis for PPGLs.

Cardiac paraganglioma with sulfur subunit B gene mutation: a case report

Background

Pheochromocytoma and paraganglioma is a rare disease with a prevalence of 0.2–0.6% in hypertensive patients from outpatient.

Case summary

A 21-year-old man complained of blood pressure elevation over one year and persistent hyperhidrosis near 5 years. In local hospital, a mass in the pericardial space with abundant blood flow was observed via echocardiography and confirmed under minimally invasive thoracotomy. With suspicion of malignant cardiac mass, the patient was recommended to transfer for further diagnosis and treatment. Combining evaluation for blood and urinary catecholamine levels, somatostatin receptor imaging, and iodine-131 metaiodobenzylguanidine scintigraphy, he was confirmed with the diagnosis of cardiac paraganglioma with blood supply from the right coronary artery identified via angiography. The cardiac tumour was then surgically resected and confirmed with a pathological diagnosis of paraganglioma. Subsequent genetic test suggested succinate dehydrogenase complex iron sulfur subunit B (SDHB) gene mutation. At 5-month follow-up, the patient was recovered with normal levels of blood catecholamines and catecholamine metabolites.

Discussion

Cardiac paraganglioma should be considered and evaluated in hypertensive patients with cardiac mass, even in non-typical population. Given a potential risk of developing malignancies, close follow-up is significant in patients with SDHB gene mutations.

Recurrence Rate of Sporadic Pheochromocytomas After Curative Adrenalectomy: A Systematic Review and Meta-analysis

BACKGROUND

Evidence on follow-up duration for patients with sporadic pheochromocytomas is absent, and current guidelines of the European Society of Endocrinology, American Association of Clinical Endocrinologists and Endocrine Surgeons, and the Endocrine Society are ambiguous about the appropriate duration of follow-up. The aim of this systematic review and meta-analysis is to evaluate the recurrence rate of sporadic pheochromocytomas after curative adrenalectomy.

MATERIALS AND METHODS

A literature search in PubMed, Embase, and the Cochrane Library was performed. A study was eligible if it included a clear report on the number of sporadic patients, recurrence rate, and follow-up duration. Studies with an inclusion period before 1990, <2 years of follow-up, <10 patients, and unclear data on the sporadic nature of pheochromocytomas were excluded. A meta-analysis on recurrence was performed provided that the heterogeneity was low (I2 < 25%) or intermediate (I2 26-75%). Hozo's method was used to calculate weighted mean follow-up duration and weighted time to recurrence with combined standard deviations (SDs).

RESULTS

A total of 13 studies, including 430 patients, were included in the synthesis. The meta-analysis results describe a pooled recurrence rate after curative surgery of 3% (95% confidence interval: 2-6%, I2 = 0%), with a weighted mean time to recurrence of 49.4 months (SD = 30.7) and a weighted mean follow-up period of 77.3 months (SD = 32.2).

CONCLUSIONS

This meta-analysis shows a very low recurrence rate of 3%. Prospective studies, including economical and health effects of limited follow-up strategies for patients with truly sporadic pheochromocytomas should be considered.

Nonselective Compared With Selective α-Blockade Is Associated With Less Intraoperative Hypertension in Patients With Pheochromocytomas and Paragangliomas: A Retrospective Cohort Study With Propensity Score Matching

Background:

Both selective and nonselective α-blockade are used for preoperative preparation in patients with pheochromocytomas and paragangliomas (PPGLs). However, the effects of different types of α-blockade on perioperative outcomes remain inconclusive. This study was designed to assess the association between the choice of α-blockade and the amount of intraoperative hypertension in patients undergoing surgery for PPGLs.

METHODS:

In this propensity-matched retrospective cohort study, data of patients who received either selective or nonselective α-blockade preoperatively and underwent surgery for PPGLs were collected. The primary end point was the time-weighted average above the systolic blood pressure (SBP) of 160 mm Hg (TWA-SBP >160 mm Hg), which was calculated as the total area of the SBP-time curve above the SBP of 160 mm Hg and divided by anesthesia duration.

RESULTS:

A total of 286 patients were included in analysis; of them, 156 received selective α-blockade and 130 nonselective α-blockade. After propensity score matching, 89 patients remained in each group. Patients who received nonselective α-blockade had a lower TWA-SBP >160 (median 0.472 mm Hg, interquartile range [IQR], 0.081–1.300) versus those who received selective α-blockade (median 1.114 mm Hg, IQR, 0.162–2.853; median difference −0.391, 95% confidence interval [CI], −0.828 to −0.032; P = .016); they also had a lower highest SBP during surgery (193 ± 24 mm Hg versus 205 ± 34 mm Hg; mean difference −12, 95% CI, −20 to −3; P = .008). Postoperative outcomes did not differ significantly between the 2 groups.

CONCLUSIONS:

For patients undergoing surgery for PPGLs, preoperative nonselective α-blockade was associated with less intraoperative hypertension when compared with selective α-blockade.

Highly Symptomatic Progressing Cardiac Paraganglioma With Intracardiac Extension Treated With 177Lu-DOTATATE: A Case Report

INTRODUCTION

Primary cardiac paragangliomas are rare tumors. Metastatic disease is even rarer. Surgical management is technically challenging, and sometimes even impossible. Available therapeutic modalities for metastatic disease include external beam radiation therapy as well as systemic treatments, namely ¹³¹I-MIBG and more recently, peptide receptor radionuclide therapy (PRRT) with ¹⁷⁷Lu-DOTATATE. To our knowledge, this is the first case of progressive unresectable cardiac paraganglioma with intracardiac extension treated with dosimetry based personalized PRRT to be reported. This case is of particular interest since it documents for the first time the efficacy, and especially the safety of the ¹⁷⁷Lu-DOTATATE PRRT in this precarious context for which therapeutic options are limited.

CASE PRESENTATION

A 47-year-old man with no medical history consulted for rapidly decreasing exercise tolerance. The investigation demonstrated an unresectable progressing metastatic cardiac paraganglioma with intracardiac extension. The patient was treated with personalized ¹⁷⁷Lu-DOTATATE PRRT and showed complete symptomatic and partial anatomical responses, with a progression-free survival of 13 months.

CONCLUSIONS

PRRT with ¹⁷⁷Lu-DOTATATE should be considered for inoperable cardiac paraganglioma. No major hemodynamic complications were experienced. Therapy resulted in safety and substantially improved quality of life.

Prognostic Nomograms for Predicting Overall Survival and Cancer-Specific Survival of Patients With Malignant Pheochromocytoma and Paraganglioma

BACKGROUND

Malignant pheochromocytoma and paraganglioma (PPGL) are rare tumors with few prognostic tools. This study aimed to construct nomograms for predicting 3- and 5-year survival for patients with malignant PPGL.

METHODS

The patient data was retrieved from the Surveillance, Epidemiology, and End Results (SEER) database. A total of 764 patients diagnosed with malignant PPGL from 1975 to 2016 were included in this study. The patients were randomly divided into two cohorts; the training cohort (n = 536) and the validation cohort (n = 228). Univariate analysis, Lasso regression, and multivariate Cox analysis were used to identify independent prognostic factors, which were then utilized to construct survival nomograms. The nomograms were used to predict 3- and 5-year overall survival (OS) and cancer-specific survival (CSS) for patients with malignant PPGL. The prediction accuracy of the nomogram was assessed using the concordance index (C-index), receiver operating characteristic (ROC) curves and calibration curves. Decision curve analysis (DCAs) was used to evaluate the performance of survival models.

RESULTS

Age, gender, tumor type, tumor stage, or surgery were independent prognostic factors for OS in patients with malignant PPGL, while age, tumor stage, or surgery were independent prognostic factors for CSS (P <.05). Based on these factors, we successfully constructed the OS and CSS nomograms. The C-indexes were 0.747 and 0.742 for the OS and CSS nomograms, respectively. In addition, both the calibration curves and ROC curves for the model exhibited reliable performance.

CONCLUSION

We successfully constructed nomograms for predicting the OS and CSS of patients with malignant PPGL. The nomograms could inform personalized clinical management of the patients.

131I-metaiodobenzylguanidine and peptide receptor radionuclide therapy in pheochromocytoma and paraganglioma

PURPOSE OF REVIEW

Pheochromocytomas and paragangliomas are rare tumors arising, respectively, from the adrenal medulla and extra-adrenal sympathetic or parasympathetic paraganglia. The main therapeutic objectives in case of metastatic disease are the reduction of tumor burden and the control of symptoms resulting from excessive catecholamine secretion. Treatment choices constitute not only a wait and see attitude, locoregional approaches, chemotherapy regiments but also radiopharmaceutical agents, and they should be discussed in a specialized multidisciplinary board. This review will briefly discuss the radiopharmaceutical modalities in patients with pheochromocytomas and paragangliomas (I-MIBG and PRRT).

RECENT FINDINGS

I-MIBG (Azedra) has received FDA approval for patients with iobenguane-scan-positive, unresectable, locally advanced or metastatic pheochromocytomas and paragangliomas who require systemic anticancer therapy, whereas peptide receptor radionuclide therapy using radiolabelled somatostatin analogues is currently performed in compassionate use, with very promising results. No prospective head-to-head comparison between the modalities has been conducted to date.

SUMMARY

Promising results have been reported for both radiopharmaceutical agents, mostly in the setting of retrospective series. No prospective head-to-head comparison between the modalities is yet available.

Malignant pheochromocytoma and paraganglioma: management options

PURPOSE OF REVIEW

Although the majority of pheochromocytoma and paraganglioma are benign, 15-17% develop metastatic disease, being present at the initial diagnosis in about 11-31% of cases. The natural course of metastasized disease is highly heterogeneous, with an overall 5-year survival rate varying between 40% and 85%. For individual patients, overall survival, progression-free survival, and clinical outcome are difficult to predict. Management of metastasized pheochromocytoma and paraganglioma is challenging. Currently available therapeutic options are surgical debulking, treatment with radiopharmaceuticals (I-MIBG, Y and Lu-DOTATATE), chemotherapy and targeted therapy.

RECENT FINDINGS

The pathogenesis of pheochromocytoma and paraganglioma (PPGL) is largely driven by genomic alterations in PPGL susceptibility genes related to three different clusters: altered pseudo-hypoxic signaling (cluster-1), altered MAP-kinase signaling (cluster-2) and altered Wnt signaling (cluster-3). Novel targeted therapies (tyrosine kinase inhibitors) and potential future therapeutic options, guided by improved knowledge about the oncogenic cluster 1-3 signaling pathways, will be discussed.

SUMMARY

Treatment of metastasized pheochromocytoma and paraganglioma remains challenging. Profiling of gene expression and methylation can serve as a powerful tool for characterizing disease clusters and for guiding targeted therapy to improve selectivity and efficacy. Current knowledge of signatures involved in molecular signaling, metabolism, and resistance mechanisms of PPGLs suggests that therapeutic regimens can be optimized to each molecular subtype.

Robotic adrenalectomy in patients with pheochromocytoma: a systematic review

Pheochromocytomas (PHEOs) are neural crest cell tumors producing catecholamines. PHEOS need to be early diagnosed and adequately managed. Adrenalectomy is the gold standard treatment of these type of tumors. There has been major improvement of surgical technologies with the development of laparoscopic and robotic systems these past several years. We conducted a review of the literature to evaluate the robotic approach for adrenalectomy for patients with PHEO.

International multicentre review of perioperative management and outcome for catecholamine-producing tumours

BACKGROUND

Surgery for catecholamine-producing tumours can be complicated by intraoperative and postoperative haemodynamic instability. Several perioperative management strategies have emerged but none has been evaluated in randomized trials. To assess this issue, contemporary perioperative management and outcome data from 21 centres were collected.

METHODS

Twenty-one centres contributed outcome data from patients who had surgery for phaeochromocytoma and paraganglioma between 2000 and 2017. The data included the number of patients with and without α-receptor blockade, surgical and anaesthetic techniques, complications and perioperative mortality.

RESULTS

Across all centres, data were reported on 1860 patients with phaeochromocytoma or paraganglioma, of whom 343 underwent surgery without α-receptor blockade. The majority of operations (78·9 per cent) were performed using minimally invasive techniques, including 16·1 per cent adrenal cortex-sparing procedures. The cardiovascular complication rate was 5·0 per cent overall: 5·9 per cent (90 of 1517) in patients with preoperative α-receptor blockade and 0·9 per cent (3 of 343) among patients without α-receptor blockade. The mortality rate was 0·5 per cent overall (9 of 1860): 0·5 per cent (8 of 517) in pretreated and 0·3 per cent (1 of 343) in non-pretreated patients.

CONCLUSION

There is substantial variability in the perioperative management of catecholamine-producing tumours, yet the overall complication rate is low. Further studies are needed to better define the optimal management approach, and reappraisal of international perioperative guidelines appears desirable.

Abdominal Ultrasound in the Detection of an Incidental Paraganglioma

Paraganglioma is a tumor that originates from neuroendocrine cells of the sympathetic or parasympathetic systems. Patients may suffer from headaches, palpitations, diaphoresis, and hypertension due to catecholamine excess or symptoms from the mass effect of the tumor. In the absence of typical symptoms of catecholamine excess, the diagnosis of a nonfunctional paraganglioma is often delayed. Herein, we report a case of a 63-year-old female patient with a nonfunctional paraganglioma which is an accidental finding during investigation of a fever. Abdominal ultrasonography incidentally detected this lesion as a complex, solid, cystic mass in the left suprarenal retroperitoneum.

The use of doxazosin before adrenalectomy for pheochromocytoma: is the duration related to intraoperative hemodynamics and postoperative complications?

Purpose

No conclusion exists for the optimum duration of preoperative administration of doxazosin (DOX) before adrenalectomy for pheochromocytoma. The purpose of this study is to investigate whether perioperative hemodynamics and postoperative outcomes are related to the duration of DOX administration.

Methods

In total, 132 patients managed preoperatively with single α-receptor blocker DOX were enrolled. All patients underwent adrenalectomy for pheochromocytoma in the Department of Urology, Peking University First Hospital, between January 2001 and July 2019. Patients were divided into three groups based on the duration of preoperative administration of DOX: group A (≤14 days), group B (15–30 days), and group C (>30 days). Patient and tumor characteristics, intraoperative hemodynamics, and postoperative outcomes were recorded and compared.

Results

These patients included 57 men and 75 women, with an average age of 48 years. Clinical characteristics, preoperative hemodynamics, medicine management and surgical approaches were comparable between the three groups. Among the three groups, we found that group C (>30 days) had the lowest intraoperative minimum heart rate [group A vs. group B vs. group C = 60 (52–67) vs. 59 (50–61) vs. 51.5 (50–58.75), p = 0.024] and highest risk of postoperative hypotension requiring vasopressor support [group A vs. group B vs. group C = 14 (20.3%) vs. 12 (27.9%) vs. 10 (50.0%), p = 0.032].

Conclusion

The current study indicated that preoperative management of pheochromocytoma with single α-receptor blocker DOX for more than 30 days after final dose adjustment might lead to intraoperative bradycardia and more postoperative hypotension requiring vasopressor support. Thus, our study does not support long-term (over 30 days) preoperative administration of pheochromocytoma with single α-receptor blocker DOX in the final dose.

Recurrent Pheochromocytoma in an Elderly Patient

Pheochromocytomas are rare neuroendocrine tumors that can affect people of all ages and are commonly diagnosed in the 4th and 5th decades of life. Familial pheochromocytomas are diagnosed mostly between the 2nd and 3rd decades of life. They can be benign or metastatic and often present as isolated tumors or along with other neuroendocrine syndromes. We present a case of an elderly man who underwent laparoscopic adrenalectomy for pheochromocytoma at the age of 60 years but developed recurrence of metastatic pheochromocytoma after ten years. We also conducted a literature review to understand the epidemiology and presentation of the tumor and to emphasize that there should be a low threshold of suspicion for timely diagnosis and management of recurrent pheochromocytoma.

MYO5B mutations in pheochromocytoma/paraganglioma promote cancer progression

Identification of additional cancer-associated genes and secondary mutations driving the metastatic progression in pheochromocytoma and paraganglioma (PPGL) is important for subtyping, and may provide optimization of therapeutic regimens. We recently reported novel recurrent nonsynonymous mutations in the MYO5B gene in metastatic PPGL. Here, we explored the functional impact of these MYO5B mutations, and analyzed MYO5B expression in primary PPGL tumor cases in relation to mutation status. Immunohistochemistry and mRNA expression analysis in 30 PPGL tumors revealed an increased MYO5B expression in metastatic compared to non-metastatic cases. In addition, subcellular localization of MYO5B protein was altered from cytoplasmic to membranous in some metastatic tumors, and the strongest and most abnormal expression pattern was observed in a paraganglioma harboring a somatic MYO5B:p.G1611S mutation. In addition to five previously discovered MYO5B mutations, the present study of 30 PPGL (8 previous and 22 new samples) also revealed two, and hence recurrent, mutations in the gene paralog MYO5A. The three MYO5B missense mutations with the highest prediction scores (p.L587P, p.G1611S and p.R1641C) were selected and functionally validated using site directed mutagenesis and stable transfection into human neuroblastoma cells (SK-N-AS) and embryonic kidney cells (HEK293). In vitro analysis showed a significant increased proliferation rate in all three MYO5B mutated clones. The two somatically derived mutations, p.L587P and p.G1611S, were also found to increase the migration rate. Expression analysis of MYO5B mutants compared to wild type clones, demonstrated a significant enrichment of genes involved in migration, proliferation, cell adhesion, glucose metabolism, and cellular homeostasis. Our study validates the functional role of novel MYO5B mutations in proliferation and migration, and suggest the MYO5-pathway to be involved in the malignant progression in some PPGL tumors.

Up to 25% of pheochromocytoma/paraganglioma (PPGL) cases develop metastatic disease with poor outcome and few treatment options. The disease mechanism is not fully understood, and to date there are no reliable markers to predict malignancy. We have recently discovered novel missense mutations in the non-conventional myosin 5 gene (MYO5B), an endosomal transport protein, which we now show enhances progression and migration in PPGLs. MYO5B mutations were preferentially found in patients with metastatic disease and SDH deficiency (germline SDHB-mutations). Abolished SDH activity result in a metabolic switch to aerobic glycolysis requiring increased glucose consumption. Since the MYO5B mutations were found to drive progression through downstream up-regulation of glucose metabolism genes, e.g. glucagon, we hypothesize that these mutations may fuel the pseudohypoxic state by altering glucose uptake in cancer cells. Our result is the first to link the myosin 5 genes to PPGL tumorigenesis. Further, it shows that the tumor progression route in PPGL is complex, with contribution from several genetic factors. An increasing number of studies show dysregulation and importance of the MYO5-proteins in cancer, but little is still known about the precise role and mechanism of mutations, hence more research in this area is needed.

Bladder Preservation for Patients With Bladder Paragangliomas: Case Series and Review of the Literature

Bladder paragangliomas are rare tumors, with no prospective studies or guidelines on the management of this disease. We present a case series of 6 patients managed with bladder preservation over a median follow-up period of 124 months. We also present a review of the recent literature on bladder paragangliomas. We aim to provide a timely synthesis of the recent evidence on bladder paragangliomas as changing paradigms necessitate individualized treatment.

Update on Pheochromocytoma and Paraganglioma from the SSO Endocrine and Head and Neck Disease Site Working Group, Part 2 of 2: Perioperative Management and Outcomes of Pheochromocytoma and Paraganglioma

This is the second part of a two-part review on pheochromocytoma and paragangliomas (PPGLs). In this part, perioperative management, including preoperative preparation, intraoperative, and postoperative interventions are reviewed. Current data on outcomes following resection are presented, including outcomes after cortical-sparing adrenalectomy for bilateral adrenal disease. In addition, pathological features of malignancy, surveillance considerations, and the management of advanced disease are also discussed.

Pheochromocytoma

Pheochromocytomas are rare tumors originating in the adrenal medulla. They may be sporadic or in the context of a hereditary syndrome. A considerable number of pheochromocytomas carry germline or somatic gene mutations, which are inherited in the autosomal dominant way. All patients should undergo genetic testing. Symptoms are due to catecholamines over production or to a mass effect. Diagnosis is confirmed by raised plasma or urine metanephrines or normetanephrines. Radiology assists in the tumor location and any local invasion or metastasis. All the patients should have preoperative preparation with α-blockers and/or other medications to control hypertension, arrhythmia, and volume expansion. Surgery is the definitive treatment. Follow up should be life-long.

Surgical approach to patients with pheochromocytoma

Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors that secrete excess catecholamines leading to secondary hypertension and cardiovascular morbidity. Once biochemical testing with either 24-hour urinary fractioned metanephrines or plasma free metanephrines confirms the diagnosis, patients are optimized with adequate hydration to maintain their intravascular volume and the appropriate antihypertensive medications are initiated for optimal blood pressure control. Genetic testing and imaging is performed to determine the extent of adrenalectomy and the optimal surgical approach. Surgical approaches include transabdominal or retroperitoneal minimally invasive approaches, and transabdominal open approaches. Factors that influence the surgical approach include germline genetic test results, the size of the tumor, body mass index, surgeon experience, and the likelihood of malignancy. The extent of adrenalectomy is based on germline genetic findings. Patients with syndromes such as von Hippel Lindau (VHL) or multiple endocrine neoplasia 2 (MEN 2) benefit from cortical-sparing adrenalectomy to avoid chronic steroid replacement and the risk of Addisonian crisis. Postoperative management includes hemodynamic monitoring and assessment for signs of hypoglycemia. Outcomes after surgery show improved blood pressure control in most patients and normalization of blood pressure in about a third of patients. Long-term follow-up is required for all patients to assess for recurrence.

Preoperative Management of Pheochromocytoma and Paraganglioma

Pheochromocytoma and paraganglioma (PPGL) are rare neuroendocrine tumors, characterized by excessive release of catecholamines (CAs), and manifested as the classic triad of headaches, palpitations, profuse sweating, and a variety of other signs and symptoms. The diagnosis of PPGL requires both evidence of excessive release of CAs and anatomical localization of CA-secreting tumor. Surgery is the mainstay of treatment for all patients with PPGL unless contraindicated. However, without proper preparation, the release of excessive CAs, especially during surgery, can result in lethal cardiovascular complications. Herein, we briefly reviewed the pathogenesis of this disease, discussed the current approaches and evidence available for preoperative management, summarizing the results of the latest studies which compared the efficacies of preoperative management with or without α adrenergic-receptor antagonists, aiming to facilitate better understanding of the preoperative management of PPGL for the physicians.

The Duration of Preoperative Administration of Single α-Receptor Blocker Phenoxybenzamine before Adrenalectomy for Pheochromocytoma: 18 Years of Clinical Experience from Nationwide High-Volume Center

Purpose

There is no consensus for the optimum duration of preoperative administration of phenoxybenzamine (PXB) before adrenalectomy for pheochromocytoma. The aim of this study is to investigate whether perioperative hemodynamics and postoperative outcomes are related to the duration of PXB administration.

Methods

In total, 102 patients managed preoperatively with single α-receptor blocker phenoxybenzamine were enrolled from 469 consecutive patients diagnosed histologically with pheochromocytoma. The patients received surgical treatment in the Department of Urology, Peking University First Hospital, between January 2001 and July 2018. All patients were divided into three groups: Group A (<14 d), Group B (14–30 d), and Group C (>30 d). Patient and tumor characteristics, intraoperative hemodynamics, and postoperative outcomes were recorded and compared among the three groups.

Results

These patients included 47 men and 55 women, with an average age of 43 years at the time of surgery. Clinical characteristics, except the status of preoperative biochemical tests (24 hr urine fractioned catecholamine or plasma-fractioned catecholamine) (p=0.020), preoperative hemodynamics, and medicine management and surgical approaches, in the three groups were comparable. Multivariate analyses demonstrated that the size of the tumor (p=0.034) was an independent risk factor for intraoperative hemodynamic instability. Among the three groups, we found no significant difference in intraoperative hemodynamics and postoperative outcomes.

Conclusion

The data from the current study indicated that the preoperative management of pheochromocytoma with single α-receptor blocker PXB for more than 2 weeks, after the final dose adjustment, could not further reduce the risk of intraoperative hemodynamic instability or postoperative complications. Thus, our study supports that 14 days would be enough for the duration of preoperative management of pheochromocytoma with single α-receptor blocker PXB in final dose.

Synergistic Highly Potent Targeted Drug Combinations in Different Pheochromocytoma Models Including Human Tumor Cultures

There are no officially approved therapies for metastatic pheochromocytomas apart from ultratrace 131I-metaiodbenzylguanidine therapy, which is approved only in the United States. We have, therefore, investigated the antitumor potential of molecular-targeted approaches in murine pheochromocytoma cell lines [monocyte chemoattractant protein (MPC)/monocyte chemoattractant protein/3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)], immortalized mouse chromaffin Sdhb-/- cells, three-dimensional pheochromocytoma tumor models (MPC/MTT spheroids), and human pheochromocytoma primary cultures. We identified the specific phosphatidylinositol-3-kinase α inhibitor BYL719 and the mammalian target of rapamycin inhibitor everolimus as the most effective combination in all models. Single treatment with clinically relevant doses of BYL719 and everolimus significantly decreased MPC/MTT and Sdhb-/- cell viability. A targeted combination of both inhibitors synergistically reduced MPC and Sdhb-/- cell viability and showed an additive effect on MTT cells. In MPC/MTT spheroids, treatment with clinically relevant doses of BYL719 alone or in combination with everolimus was highly effective, leading to a significant shrinkage or even a complete collapse of the spheroids. We confirmed the synergism of clinically relevant doses of BYL719 plus everolimus in human pheochromocytoma primary cultures of individual patient tumors with BYL719 attenuating everolimus-induced AKT activation. We have thus established a method to assess molecular-targeted therapies in human pheochromocytoma cultures and identified a highly effective combination therapy. Our data pave the way to customized combination therapy to target individual patient tumors.

Current Management of Pheochromocytoma/Paraganglioma: A Guide for the Practicing Clinician in the Era of Precision Medicine

Pheochromocytomas and paragangliomas (PCC/PGLs) are rare, mostly catecholamine-producing neuroendocrine tumors of the adrenal gland (PCCs) or the extra-adrenal paraganglia (PGL). They can be separated into three different molecular clusters depending on their underlying gene mutations in any of the at least 20 known susceptibility genes: The pseudohypoxia-associated cluster 1, the kinase signaling-associated cluster 2, and the Wnt signaling-associated cluster 3. In addition to tumor size, location (adrenal vs. extra-adrenal), multiplicity, age of first diagnosis, and presence of metastatic disease (including tumor burden), other decisive factors for best clinical management of PCC/PGL include the underlying germline mutation. The above factors can impact the choice of different biomarkers and imaging modalities for PCC/PGL diagnosis, as well as screening for other neoplasms, staging, follow-up, and therapy options. This review provides a guide for practicing clinicians summarizing current management of PCC/PGL according to tumor size, location, age of first diagnosis, presence of metastases, and especially underlying mutations in the era of precision medicine.

Approach to Surgery for Cardiac Tumors: Primary Simple, Primary Complex, and Secondary

Cardiac tumors are rare. Most surgeons will encounter few primary cardiac tumors outside of myxomas. This article offers the authors' approach to simple and complex primary and secondary cardiac tumors. Symptoms of primary cardiac tumors are primarily determined by tumor size and anatomic location. Most simple primary tumors and some complex primary tumors are best managed by surgical resection. Secondary tumors are 30 times more frequent than primary cardiac tumors. Surgical resection of secondary tumors is rational in a few highly selected patients. For complex primary and secondary tumors, the authors recommend referral to an experienced multidisciplinary cardiac tumor team.